In the coming twelve months we will collect and evaluate 50 to 100 "normal" aortae from human autopsy specimens of various age groups. We have the cooperation of the local hospitals in this study. These aortae will be evaluated for the integrity of their elastic tissue which will be expressed as a degradation index, sampling at least 20 areas of each aorta. The elastin will be isolated by nondegradative methods and the intactness of each preparation evaluated by the Edman reaction and expressed as nanomoles of each amino acid detected as compared to total micromoles of the amino acid acid present in that elastin specimen. Collection of the specimens will be a large part of the work in this project. Automation of the methodologies described above makes the chemical determinations relative simple.